Catalysing (organo-)catalysis: Trends in the application of machine learning to enantioselective organocatalysis

• Stefan P. Schmid,
• Leon Schlosser,
• Frank Glorius and
• Kjell Jorner

Beilstein J. Org. Chem. 2024, 20, 2280–2304, doi:10.3762/bjoc.20.196

• ]. Despite the prominence of organocatalytic reactions, catalyst development has so far mostly been conducted guided by intuition of skilled organic chemists. Given that organocatalytic reactions are governed by different competing interactions, the influence of a change in molecular structure is often non

• data needs to be provided in a machine-readable way. Unlike chemists who typically use drawings of Lewis structures to represent molecules, computers require a numerical representation of the molecular structure. Since the information that describes the input directly influences what relationships a

• successfully applied for predictive modelling in organocatalysis. In contrast to the representations through graphs, or SMILES, which can be directly obtained from the molecular structure, the selection of appropriate descriptors is problem-specific and requires knowledge about the fundamental interactions

Understanding X-ray-induced isomerisation in photoswitchable surfactant assemblies

• Beatrice E. Jones,
• Camille Blayo,
• Jake L. Greenfield,
• Matthew J. Fuchter,
• Nathan Cowieson and
• Rachel C. Evans

Beilstein J. Org. Chem. 2024, 20, 2005–2015, doi:10.3762/bjoc.20.176

• spatiotemporal control. To build responsive materials, surfactants are particularly attractive due to their ability to self-assemble into different morphologies depending on their molecular structure and chemical environment. To that end, photoswitchable chromophores can be incorporated into amphiphilic

Oxidative fluorination with Selectfluor: A convenient procedure for preparing hypervalent iodine(V) fluorides

• Samuel M. G. Dearman,
• Xiang Li,
• Yang Li,
• Kuldip Singh and
• Alison M. Stuart

Beilstein J. Org. Chem. 2024, 20, 1785–1793, doi:10.3762/bjoc.20.157

• ) under a nitrogen atmosphere and the dichloromethane was removed in vacuo to afford difluoroiodane 6 as a pale orange solid (0.58 g, 90%). Bicyclic difluoro(aryl)-λ5-iodanes. Molecular structure of difluoroiodane 6 showing 50% displacement ellipsoids. Stability of difluoroiodane 6 in air in dry CD3CN

Ugi bisamides based on pyrrolyl-β-chlorovinylaldehyde and their unusual transformations

• Alexander V. Tsygankov,
• Vladyslav O. Vereshchak,
• Tetiana O. Savluk,
• Serhiy M. Desenko,
• Valeriia V. Ananieva,
• Oleksandr V. Buravov,
• Yana I. Sakhno,
• Svitlana V. Shishkina and
• Valentyn A. Chebanov

Beilstein J. Org. Chem. 2024, 20, 1773–1784, doi:10.3762/bjoc.20.156

• . Molecular structure of ethyl (Z)-4-(3-(N-(4-bromophenyl)-2-chloroacetamido)-4-(tert-butylamino)-1-chloro-4-oxobut-1-en-1-yl)-3,5-dimethyl-1H-pyrrole-2-carboxylate (8c) according to the X-ray diffraction study. Non-hydrogen atoms are presented as thermal ellipsoids with 50% probability. Molecular structure

• of ethyl (E)-4-(4-(tert-butylamino)-3,4-dioxobut-1-en-1-yl)-3,5-dimethyl-1H-pyrrole-2-carboxylate (10d) according to X-ray diffraction data. Non-hydrogen atoms are presented as thermal ellipsoids with 50% probability. Molecular structure of ethyl 4-(3-(N-(4-bromophenyl)-2-chloroacetamido)-4-(tert

Photoswitchable glycoligands targeting Pseudomonas aeruginosa LecA

• Yu Fan,
• Ahmed El Rhaz,
• Stéphane Maisonneuve,
• Emilie Gillon,
• Maha Fatthalla,
• Franck Le Bideau,
• Guillaume Laurent,
• Samir Messaoudi,
• Anne Imberty and
• Juan Xie

Beilstein J. Org. Chem. 2024, 20, 1486–1496, doi:10.3762/bjoc.20.132

• deactivation of biological function. It also offers the potential to change the properties of defined molecules in biological systems with minimal disturbance to the rest of the system. Photoswitchable ligands, i.e., the incorporation of light-responsive moieties into a drug-like molecular structure, allow

Rapid construction of tricyclic tetrahydrocyclopenta[4,5]pyrrolo[2,3-b]pyridine via isocyanide-based multicomponent reaction

• Xiu-Yu Chen,
• Ying Han,
• Jing Sun and
• Chao-Guo Yan

Beilstein J. Org. Chem. 2024, 20, 1436–1443, doi:10.3762/bjoc.20.126

• produced in the reaction, while the other diastereomers were not detected. In order to elucidate the relative configuration of the obtained compounds, the molecular structure of the compound 4a was determined by single crystal X-ray diffraction (Figure 1). From Figure 1, it can be seen that the fused

• can be performed with a wide variety of substrates. The molecular structure of the compound 6g was determined by single crystal X-ray diffraction method (Figure 2). The o-methoxyphenyl group exists on the trans-position of the fused pyrrolidine unit. The methoxycarbonyl group also exists on the cis

• . Molecular structure of compound 4a. Molecular structure of compound 6g. Proposed reaction mechanism. Optimizing reaction conditionsa. The synthesis of the tricyclic compounds 4a–ta. The synthesis of the tricyclic compounds 6a–ka. Supporting Information The crystallographic data of the compounds 4a (CCDC

A comparison of structure, bonding and non-covalent interactions of aryl halide and diarylhalonium halogen-bond donors

• Nicole Javaly,
• Theresa M. McCormick and
• David R. Stuart

Beilstein J. Org. Chem. 2024, 20, 1428–1435, doi:10.3762/bjoc.20.125

• electronic structure (bonding) and molecular structure (geometry) in diarylhalonium salts. We found a periodic trend with respect to the percentage of s- and p-orbital character used by the central atom to bond to the aryl substituents for a series of isoelectronic diaryl chalcogen and diarylhalonium

Synthesis of indano[60]fullerene thioketone and its application in organic solar cells

• Yong-Chang Zhai,
• Shimon Oiwa,
• Shinobu Aoyagi,
• Shohei Ohno,
• Tsubasa Mikie,
• Jun-Zhuo Wang,
• Hirofumi Amada,
• Koki Yamanaka,
• Kazuhira Miwa,
• Naoyuki Imai,
• Takeshi Igarashi,
• Itaru Osaka and
• Yutaka Matsuo

Beilstein J. Org. Chem. 2024, 20, 1270–1277, doi:10.3762/bjoc.20.109

• -withdrawing substituents. Computational studies with density functional theory revealed the unique vibrations of the thioketone group in FIDS. The molecular structure of FIDS was confirmed by single-crystal X-ray analysis. Bulk heterojunction organic solar cells using three evaporable fullerene derivatives

Competing electrophilic substitution and oxidative polymerization of arylamines with selenium dioxide

• Vishnu Selladurai and
• Selvakumar Karuthapandi

Beilstein J. Org. Chem. 2024, 20, 1221–1235, doi:10.3762/bjoc.20.105

• structure, it self-organized through π–π interaction between the oxamide motif and the aryl π-framework. Further, the CH…O=C interaction facilitated the formation of ladder-like packing in the solid state (Figure S36, Supporting Information File 1). The molecular structure of oxamide 13 is shown in Figure 3

• (Figure S37, Supporting Information File 1). The dipolar characteristics of the ester group appeared to assist the molecular layer-by-layer stacking seen in the crystal packing. The molecular structure of the quinone derivative 10 is shown in Figure 4. It crystallized in a monoclinic crystal system in the

• space group C2/c. The molecular structure of the diorganyl monoselenide 11 is shown in Figure 5. It crystallized in a triclinic crystal system in the space group P−1. The C–Se–C bond angle was found to be 99.01°. Both inter- and intramolecular hydrogen bonding were noted in the structure (Figure S39

Novel route to enhance the thermo-optical performance of bicyclic diene photoswitches for solar thermal batteries

• Akanksha Ashok Sangolkar,
• Rama Krishna Kadiyam and
• Ravinder Pawar

Beilstein J. Org. Chem. 2024, 20, 1053–1068, doi:10.3762/bjoc.20.93

• impose a serious limitation for their practical applications [8][9][10][11][12][13]. It is believed that the rational design of the molecular structure can assist to endow all the necessary properties in a single photoswitch [14]. Therefore, engineering of novel photochromic couples with an intention to

Spin and charge interactions between nanographene host and ferrocene

• Akira Suzuki,
• Yuya Miyake,
• Ryoga Shibata and
• Kazuyuki Takai

Beilstein J. Org. Chem. 2024, 20, 1011–1019, doi:10.3762/bjoc.20.89

• vibration [30]. These spectra also indicate the successful introduction of FeCp2 to ACFs and that most FeCp2 maintains its molecular structure inside the nanographene host in both of FeCp2-ACFs-55 and FeCp2-ACFs-150. Moreover, the higher peak intensities of FeCp2 molecular vibrations in the spectrum for

Organic electron transport materials

• Joseph Cameron and
• Peter J. Skabara

Beilstein J. Org. Chem. 2024, 20, 672–674, doi:10.3762/bjoc.20.60

• react with acceptors to produce reducing radical species, capable of reducing organic electron transport materials with a low electron affinity [4][5]. It is not only in modifying the molecular structure to improve the electron accepting ability that there is innovation in new organic electron transport

A laterally-fused N-heterocyclic carbene framework from polysubstituted aminoimidazo[5,1-b]oxazol-6-ium salts

• Andrew D. Gillie,
• Matthew G. Wakeling,
• Bethan L. Greene,
• Louise Male and
• Paul W. Davies

Beilstein J. Org. Chem. 2024, 20, 621–627, doi:10.3762/bjoc.20.54

• the C(oxazole)–N(sulfonamide) bond. No coalescence is observed at up to 110 °C indicating that these motifs might be useful as a robust atropisomeric system. The molecular structure of 13 and 14 have been unambiguously determined by single crystal X-ray diffraction (Scheme 2) [28]. The N–metal

Possible bi-stable structures of pyrenebutanoic acid-linked protein molecules adsorbed on graphene: theoretical study

• Yasuhiro Oishi,
• Motoharu Kitatani and
• Koichi Kusakabe

Beilstein J. Org. Chem. 2024, 20, 570–577, doi:10.3762/bjoc.20.49

• . Rotations around each bond can also happen and we expect similar steric hindrance effects to appear. Mechanical properties of PBA-linked molecular structure on graphene Here, we discuss possible conformations of the PBA-linked molecule. Would a similar activation barrier-type potential energy surface be

• conformation 1, 2, and the conformation at the saddle point, we measured the dihedral angles and the distance between two hydrogen atoms using Xcrysden [10]. (a) Molecular structure of 1-pyrenebutanoic acid succinimidyl ester (PASE). The black, white, red, and blue balls represent C, H, O, and N atoms

Synthesis of photo- and ionochromic N-acylated 2-(aminomethylene)benzo[b]thiophene-3(2Н)-ones with a terminal phenanthroline group

• Vladimir P. Rybalkin,
• Sofiya Yu. Zmeeva,
• Lidiya L. Popova,
• Irina V. Dubonosova,
• Olga Yu. Karlutova,
• Oleg P. Demidov,
• Alexander D. Dubonosov and
• Vladimir A. Bren

Beilstein J. Org. Chem. 2024, 20, 552–560, doi:10.3762/bjoc.20.47

• products 3a–c were comprehensively characterized by IR, 1Н and 13C NMR spectroscopy, HRMS (Supporting Information File 2) as well as by X-ray diffraction analysis. The molecular structure of 3b is shown in Figure 3. The crystal data, details of the data collection and refinements for 3b as well as complete

• of compound 2b in acetonitrile before (1) and after 15 s (2), 35 s (3), 75 s (4), 2.5 min (5) and 5 min (6) of irradiation with light of 436 nm (c 5.0 × 10−5 mol·L−1). Molecular structure of O-acylated isomer 3b. Thermal ellipsoids are drawn at the 50% probability level. Fragment of the molecular

Synthesis of 2,2-difluoro-1,3-diketone and 2,2-difluoro-1,3-ketoester derivatives using fluorine gas

• Alexander S. Hampton,
• David R. W. Hodgson,
• Graham McDougald,
• Linhua Wang and
• Graham Sandford

Beilstein J. Org. Chem. 2024, 20, 460–469, doi:10.3762/bjoc.20.41

• -generated N-fluoroammonium ion 7 to form 2-fluoro- and 2,2-difluoro-1,3-dicarbonyl products. Molecular structure of 2,2-difluoro-1,3-diphenylpropane-1,3-dione (3a). Crystal packing structure of 3f as determined by SXRC. Molecular structure and crystal packing of 5e as determined by SXRC. Monofluorination of

Facile approach to N,O,S-heteropentacycles via condensation of sterically crowded 3H-phenoxazin-3-one with ortho-substituted anilines

• Eugeny Ivakhnenko,
• Vasily Malay,
• Pavel Knyazev,
• Nikita Merezhko,
• Nadezhda Makarova,
• Oleg Demidov,
• Gennady Borodkin,
• Andrey Starikov and
• Vladimir Minkin

Beilstein J. Org. Chem. 2024, 20, 336–345, doi:10.3762/bjoc.20.34

• widened the scope and provided an access to derivatives of N,O- and N,S-heteropentacyclic quinoxalinophenoxazine, triphenodioxazine and oxazinophenothiazine systems. Keywords: 3H-phenoxazin-3-one; fluorescence; molecular structure; pentacyclic heterocycles; synthesis; Introduction 3H-Phenoxazin-3-one

• molecular structure of 5c was also determined using X-ray crystallography (Figure 4). We assumed that the scope of the reaction shown in Scheme 3 could be expanded via replacement of one of the amino groups of o-phenylenediamine by another strong nucleophilic center. It was earlier found [23] that

• -311++G(d,p) level) and distribution of electronic density in 6,8-di-tert-butyl-3H-phenoxazin-3-one (1): Mulliken charges and molecular electrostatic potential (MEP, isovalue = 0.004). Molecular structure of 6,8-di-tert-butyl-2-(o-nitrophenylamino)-3H-phenoxazin-3-one (4f). a) Selected bond distances

Photochromic derivatives of indigo: historical overview of development, challenges and applications

• Gökhan Kaplan,
• Zeynel Seferoğlu and
• Daria V. Berdnikova

Beilstein J. Org. Chem. 2024, 20, 228–242, doi:10.3762/bjoc.20.23

• ]. After the determination of the molecular structure of indigo in 1883, various precursors such as isatin (1), cinnamic acid (2), 2-nitrobenzaldehyde (3), aniline (4), 2-aminobenzoic acid (5), phenylglycine (6), 1-(1H-indol-1-yl)ethan-1-one (7) and indole (8) have been used in the synthesis (Figure 1) [4

• thermal half-lives of the photoisomers range from seconds to days. Detailed photophysical and photochemical studies have provided insight into the photoswitching mechanisms of indigo derivatives and enabled control of their photochemical properties through targeted design of the molecular structure. The

Comparison of glycosyl donors: a supramer approach

• Anna V. Orlova,
• Nelly N. Malysheva,
• Maria V. Panova,
• Nikita M. Podvalnyy,
• Michael G. Medvedev and
• Leonid O. Kononov

Beilstein J. Org. Chem. 2024, 20, 181–192, doi:10.3762/bjoc.20.18

• putative participation in stabilization [52][53] of the glycosyl cation. More importantly, in our opinion, this result indicates the existence of unexpected difficulties in the determination of relative reactivities of glycosyl donors (vide infra). Discussion It is generally believed that the molecular

• structure and the reaction mechanism are the keys to understanding chemical reactivity and selectivity [65][66][67]. In the area of carbohydrate chemistry, a lot of efforts are devoted to finding relationships between the fine details of molecular structures of both glycosylation partners (glycosyl donor

Using the phospha-Michael reaction for making phosphonium phenolate zwitterions

• Matthias R. Steiner,
• Max Schmallegger,
• Larissa Donner,
• Johann A. Hlina,
• Christoph Marschner,
• Judith Baumgartner and
• Christian Slugovc

Beilstein J. Org. Chem. 2024, 20, 41–51, doi:10.3762/bjoc.20.6

• in these cases (Supporting Information File 1, Figures S54 and S74). Crystal structures The solid-state structures of 2a and 2f were determined by single-crystal X-ray diffraction. The crystals were grown from concentrated solutions in toluene. A representation of the molecular structure of 2a is

• on the solid-state structure of 2a and the numbering scheme of the phenolate moiety. a) Molecular structure of 2a, hydrogen atoms omitted for clarity, thermal ellipsoids drawn at 30% probability level. Selected distances (Å) and angles (deg): P1–C6 = 1.758(2), P1–C15 = 1.824(2), P1–C18 = 1.814(2), P1

NMRium: Teaching nuclear magnetic resonance spectra interpretation in an online platform

• Luc Patiny,
• Hamed Musallam,
• Alejandro Bolaños,
• Michaël Zasso,
• Julien Wist,
• Metin Karayilan,
• Eva Ziegler,
• Johannes C. Liermann and
• Nils E. Schlörer

Beilstein J. Org. Chem. 2024, 20, 25–31, doi:10.3762/bjoc.20.4

• , and finally assign to a molecular structure. Students can then save the result of their work as .nmrium and submit it to the teacher who can then assess their solution and their solving strategy. Conclusion To the best of our knowledge, the software NMRium presented in this paper provides the first

Biphenylene-containing polycyclic conjugated compounds

• Cagatay Dengiz

Beilstein J. Org. Chem. 2023, 19, 1895–1911, doi:10.3762/bjoc.19.141

• with BBr3. In the final step, the integration of mesityl groups into the molecular structure, resulted in the production of both compounds 77 and 78, adopting v and z-configurations, respectively, in a 4 to 1 ratio. The synthesis of linear compound 84, characterized by a more extensive conjugated

Controlling the reactivity of La@C₈₂ by reduction: reaction of the La@C₈₂ anion with alkyl halide with high regioselectivity

• Yutaka Maeda,
• Saeka Akita,
• Mitsuaki Suzuki,
• Michio Yamada,
• Takeshi Akasaka,
• Kaoru Kobayashi and
• Shigeru Nagase

Beilstein J. Org. Chem. 2023, 19, 1858–1866, doi:10.3762/bjoc.19.138

• between the La@C2v-C82 adducts (2a–c, 3a–c, and 4a–c) [19] and the Ce@C2v-C82(CH2C6H3Me2) isomers [25] reported by Takano et al. was observed. Based on this observation, the plausible addition sites of 2a–c, 3a–c, and 4a–c were estimated to be at the C14, C10, and C18 positions. The molecular structure of

• ) an enlarged part view of blue region in (a). (c) Spin density of La@C2v-C82 as a function of its POAV values [34][35]. (d) Molecular structure of La@C2v-C82 and numbering carbon atoms. Reaction of the La@C2v-C82 anion with benzyl bromide derivatives. Charge densities and POAV values of carbon atoms

Selectivity control towards CO versus H₂ for photo-driven CO₂ reduction with a novel Co(II) catalyst

• Lisa-Lou Gracia,
• Philip Henkel,
• Olaf Fuhr and
• Claudia Bizzarri

Beilstein J. Org. Chem. 2023, 19, 1766–1775, doi:10.3762/bjoc.19.129

• ). Efforts to selectively achieve one polymorph, through differentiated crystallization processes, were unsuccessful. When analyzing the molecular structure in both crystals, the cobalt core is hexacoordinated, as expected. The two isothiocyanate ions are oriented cis to each other and trans to the

Charge carrier transport in perylene-based and pyrene-based columnar liquid crystals

• Alessandro L. Alves,
• Simone V. Bernardino,
• Carlos H. Stadtlober,
• Edivandro Girotto,
• Giliandro Farias,
• Rodney M. do Nascimento,
• Sergio F. Curcio,
• Thiago Cazati,
• Marta E. R. Dotto,
• Juliana Eccher,
• Leonardo N. Furini,
• Hugo Gallardo,
• Harald Bock and
• Ivan H. Bechtold

Beilstein J. Org. Chem. 2023, 19, 1755–1765, doi:10.3762/bjoc.19.128

• benzo[ghi]perylene-hexacarboxylic trialkylimide and 2 a dinaphtho[2,1-a;1,2-i]pyrene-tetracarboxylic dialkylimide, both with asymmetrically branched alkyl swallow-tails derived from 7-aminohexadecane (Scheme 1 illustrates their molecular structure). In Table 1, we show the thermal characteristics and